Compressed: No?

ExitiumMachina

All the textures I edit come out with: Resource: No; in SparkIV. That and after editing about 3 textures I get a memory error. What am I doing wrong here? Keep in mind this is the first time I've skinned since GTAIII so I could be saving it wrong, but I do save the files as .png...is there something else I'm missing?